This is my first post, but I need help with a problem! I had a pond dug in 1997, which is basically a 1 acre hole in the ground about 22 feet deep and the excavated material was hauled away for roadway embankment. It will fill with a 3" rain, no problem. But it loses water at a rate of about 3 feet a month. In one corner, while excavating this pond I encountered a rock shelf and I suspect this is my problem area, but I really don't know. Now that the pond is full from the recent heavy rains, the rock shelf is under 10' or so of water. Is there any way for me to determine if in fact this is my problem area, and will bentonite cast into the water ever accummulate in the seeping area and form a seal? Thanks!

Welcome mykol. It didn't take you long to come over from the THF.

If the rock shelf is the problem the water loss should slow down once it is out of water. The best thing to do would be to cover up the rock with a couple feet of compacted clay.

Bentonite needs to be tilled into the soil to be effective.

Thanks Chris! Yea, I have to again give my thanks to you THF guys for pointing me in the right direction on about any of my questions!

Does anybody know how I can determine if this rock shelf is actually the location of the leak? The rock shelf begins about 10' from the surface but I am not sure how deep it goes. The pond will continue to lose water till it is really pretty low but I don't see any voids in the side slopes in this area when it is low.

If anyone will know, Otto will... He usually comes on really early in the morning. Check back over the next couple of days and he should weigh in.

Do you see the result of the leak "downstream"?

Mykol, which direction and distance from Bonham?
What kind of soil?
Describe color and density of rock shelf?
If it a whitish chalky limestone, it is likely a porous Cretaceous carbonate that could be a few feet thick or a few hundred feet, and soak up water like a sponge.
If so, will have to be sealed with clay as experts will advise.

I am located about 10 miles SW of Bonham on SH 121, about half way between Trenton and Randolph. The surface soil is black gumbo, which is a very plastic clay. But the rock encountered is the white/yellow chalky limestone. Please keep the advice comming! Thanks

Mykol,

Is your pond the one with the steep banks and a dock on the north shore?

Yes Chris, it is!

Cool. The next time I go by there I will let you know. If you don't get it fixed by then maybe we can look at it and come up with a plan.

That's whatI thought.
It is a very porous limestone and will have to be sealed.
That blackland gumbo should do the trick but let the experts make the call.

I would think the rock is your problem, but sometimes there is also other pockets of material in the ground that could be causing your pond to drain water. Gravel, iron ore and sand are all good ways to drain water.

The water will drain down to the leak. Does it drain all the way down to the bottom? Or does it stop at a certain point? Where it stops, is where your leak ends.

Once you determine where the leak is, you can patch it with a few feet of compacted clay.

Eddie

Thanks a bunch guys! The pond never goes completely dry, I would guess the water depth to be 6 to 8' deep when it pretty well stabilizes. But what's bad is that's about 15' down from level full.

And Chris, I appreciate the offer! Please do let me know when you may be comming through the area. Thanks again to all!

Rocks and sand create an aquifer effect. They are like a spring that can give or take water. The problem is that you have no idea how far it extends. So, you have to cover the rocks with good, well packed, clay.

Mykol
Welcome to the forum I like Chris And George are close to your pond..

The black gumbo will seal just about anything.
Keep a close eye on the level it will drop until it hits good material. The repair cannot be done with water in it anyway.

Measure how fast it goes down and keep us posted.

OK, I was right about Otto checking in within the next couple days just not the time! Darn...

Thanks Otto. I will monitor the drop and report back.

Problem since last week is it just keeps overflowing! Think I have an anti-leak....!